The present invention pertains to a bellows, as it is installed between two vehicles which are connected to one another in an articulated manner. Thus, passengers can reach from one vehicle to another via a transition platform, without their being exposed to weather and relative wind unprotected (e.g., U.S. Pat. No. 4,860,665, FIG. 1, corresponding to FIG. 1 of the present application).
Such a bellows has a top and two side walls as well as a transition area between the top and each side wall. If necessary, the lower ends of the side walls are connected to one another under the transition platform by a bellows bottom (e.g., EP 275,365). Corresponding to the bellows top, the bellows bottom is connected with one of the side walls on each end via a transition area.
Such a bellows is usually designed such that the bottom is divided at a seam in the center running in the longitudinal direction, and a fold runs from one edge of the separation line via the associated bellows bottom half, a lower transition area, a bellows side wall, an upper transition area, the bellows top, another upper transition area, the second bellows side wall, another lower transition area, and finally, the other bellows bottom half to the other edge of the seam of the bellows bottom (EP 114,913). If such a bellows is installed, then it is connected along the seam by suitable seals.
Normally, such a bellows is composed of individual strips, each of which has the cross section of a V or even, for example, of a semicircle. Two consecutive strips are held together on the edges by frames (e.g., U.S. Pat. No. 4,690,421). Along the entire length in the circumferential direction of the bellows, the individual strips or folds actually have the same material and deformation properties. By this it is meant that, the bellows is rather rigid in the transition area between the side walls and the top or bottom. This is undesirable. Therefore, it has already been proposed to especially design the bellows in the transition areas in order to make the "bellows corners" softer, than they actually are. In order to achieve this, the individual strips can be composed of individual sections which are consecutive in the bellows circumferential direction, whereby a material is used for the transition areas, said material being softer than the material for the side walls, the top and the bottom (EP 275,365). A corresponding effect can also be achieved in that additional folds are installed in the transition areas, by means of which the bellows is also softer in the transition areas, than would otherwise be the case (DE 26 17 931).
Finally, a process is also known for hanging another wall in front of the side walls of a bellows, in order to have an especially good sound insulation in the area of the side walls or in order to have an invisible space between the bellows side wall and the curtain type wall for the passengers, in which space function elements can be housed (U.S. Pat. No. 4,690,421).